Metal reacts directly when it comes into contact with reactive gases such as oxygen, water vapor (gaseous state), and carbon dioxide gas, and the metal is consumed while forming a solid film of reaction products (oxides) on the metal surface. This is called dry corrosion.
Countermeasures
After a certain period of use, it is necessary to perform the following inspections and evaluations to prevent fracture:
- Subcategory: Dry Corrosion
- Damage mode: Metal loss (Thinning), Cracks (Hydrogen Embrittlement)
- Inspection: Visual inspection, measurement of metal thickness.
- Evaluation: Prediction of metal thinning rate, assessment of remaining service life.
- Actions: Establish criteria for metal buildup repair, crack removal, component replacement, and material change based on the assessment.
There are many detail mechanisms for dry corrosion. Followings are recommended for plant maintenance countermeasures;
> To confirm the detail mechanisms by using FPAI Class 2
> To implement the countermeasures suggested